This invention relates to the field of prophylactics known as micro-condoms, penile caps or glans sheaths as defined by the United States Food and Drug Administration.
Prophylactic devices which attach only to the glans penis are identified by the United States Food and Drug Administration as glans sheaths. These devices attach either by adhesive means or by restraining means such as a constricting grip. For those devices which adhere to the penis only about the tip, the reservoir volume of the sheath must be large enough in size to contain the quantity of ejaculate discharged into the reservoir. Roll-down condom prophylactics do not have this reservoir volume issue as the ejaculate discharge can fill into the full volume of the roll-down condom. A glans sheath reservoir which is unable to accomodate the produced volume of ejaculate becomes pressurized by the strong contractions of the muscles producing the ejaculation. This fluid pressure can easily compromise the bondline of the adhesive securing the glans sheath to the glans penis.
The instant invention is a glans sheath designed to have a reservoir volume capable of containing approximately 8 cc""s of fluid. The reservoir is packaged such that the reservoir is not distally positioned relative to the bonding flange once packaged, but is inverted proximally and folded over upon itself. Inverting and folding the reservoir evacuates air from the reservoir and protects the reservoir prior to its deployment.
Glans sheath prophylactics such as U.S. Pat. Nos. 3,677,225, 3,648,700, 4,320,752, 4,821,742, 4,869,269, 5,102,405, and 5,421,350 all have a fundamental flaw as a glans sheath. All of these devices provide no method of evacuating air from the resevoir volume during the manufacturing operation. Additionally, these devices do not take measures to ensure that the evacuated air remains removed prior to glans bonding. Without this critical step of evacuating the reservoir air prior to bonding, all of the ejaculate discharge entering into the reservoir volume competes with trapped air for space and this pressurizes the reservoir above ambient atmospheric pressure. This overpressure is great enough to cause localized failure of the bonded area of the flange of the glans sheath. This localized failure is identified as a small fissure separation of the adhered flange from the glans. Seminal discharge erupts through this small fissure, completely defeating the contraceptive intention of the device. Reservoir air evacuation is not an exercise that should be left to the user bonding the device to the glans. Evacuation should be included as a manufacturing step. The instant invention incorporates reservoir evacuation and reservoir packaging into the manufacturing process.
U.S. Pat. No. 5,458,114 addresses both design issues of forming a reservoir large enough to contain a typical seminal discharge volume and packaging this reservoir volume to ensure that air evacuated from the reservoir volume remains evacuated prior to bonding. This design has other flaws.
In U.S. Pat. No. 5,458,114 the protective retaining structure packaging the reservoir of the device must be mechanically affixed to the distal surface of the sheath flange. This manufacturing step lowers the reliability of the device in that the retaining structure must be mechanically attached to the bowl structure. Should the retaining structure physically separate from the bowl during coitus, it would have to be retrieved by a medical professional if it were to become lodged in a body cavity. Further, the retaining structure is designed to have a star shaped pattern which the bladder must be forced through as the bladder deploys. Depending on the rigidity of the retaining structure, this material will oppose the bladder attempting to deploy itself and the weaker path of resistance for the pressurized ejaculate becomes the bondline of the bowl adhered to the skin of the glans. Should the bondline fail by the creation of a fissure as described, the contraceptive intention of the patented device is defeated.
U.S. Pat. No. 5,477,865 is a roll-down prophylactic which also inverts the reservoir during its manufacture. The fundamental flaw with this design is that the inverted reservoir cannot be rolled up or folded onto itself once inverted. This leaves the design with two options. The design can have a small enough reservoir that it is not necessary to roll or fold the reservoir to avoid damage to the reservoir during coitus. In this case, the reservoir will likely re-invert itself back to its original distal position once the user tries to apply the condom simply from air pressure inside the condom. A condom with a small reservoir as described does not offer much ejaculate containment volume and is essentially a commercially available condom with the small reservoir tip turned inside out. Ideally an inverted reservoir would be large enough to contain greater than 5 cc""s of fluid. A reservoir this large should be folded or somehow packaged to remain at the tip of the glans near the urethral opening once inverted. Without some variation of a restraining mechanism, such as a flap, to keep the inverted reservoir folded up, the reservoir will spring back to its elongated shape and will face proximally. Once the reservoir is sprung and extended proximally, the user can only push the reservoir off to the side during roll down application. Pushed off to the side, the reservoir will extend down the interior length of the condom rolled down onto the penis and is then firmly wedged between the glans or shaft of the user""s penis and the interior wall of the condom rolled onto the penis. Wedged in this fashion, the reservoir is completely useless as it cannot be deployed because it is constrictively trapped between the condom sidewall and the user""s penis. This is also an unsatisfactory option.
The instant invention discloses a glans sheath device which has a large reservoir volume to avoid overpressurization and the device is packaged so as to evacuate, fold and protect the reservoir without the addition of any external retaining structures to compromise reliability. During manufacturing the reservoir is inverted from its deployed distal position relative to the bonding flange of the glans sheath and instead lies in a compacted state facing the proximal direction of the device. In this orientation the reservoir is evacuated, folded and secured in place. By properly evacuating and folding the large reservoir during manufacturing of the instant invention, the reservoir is able to properly deploy when seminal discharge floods the reservoir yet the reservoir remains properly evacuated and constrained throughout coitus until reservoir flooding occurs.
Another issue which must be addressed is a method for handling a very pliable flange material. U.S. Pat. No. 6,098,625 by Winkler discloses a tool for tautly restraining the flange of that invention but does not utilize an efficient two-piece tool design as does the present invention. Winkler""s invention must rely on proper separation between the tool and the flange after bonding the flange to the glans. There is also a likelihood that Winkler""s design presents the opportunity for the flange to separate from the rigid tool before successful bonding which allows the creation of crevasses in the unbonded flange. The restraining legs of the instant invention differ in purpose from the force distribution strips of Winkler""s design. Winkler intends the force distribution strips of U.S. Pat. No. 6,098,625 to remain affixed to the flange material to distribute tensile forces pulling the flange away from the glans penis during coitus.
The invented device is a glans sheath contraceptive which covers only the portion of the glans penis immediately surrounding the urethral opening. The device provides an adhesive coated annular flange as a means of attaching to the glans penis a collapsed, proximally oriented, folded reservoir capable of deploying when pressurized and able to contain ejaculate once deployed.